It’s a sunny day with a nippy on-shore breeze. Plymouth Hoe sparkles under the bright blue sky as I walk towards the railings. And then it appears, the turquoise Art Deco joy that is Tinside Lido, curving out over the sea, flags waving, fountain spewing from its centre, positively screaming ‘Dive In’! This isn’t a normal swimming pool: it’s almost circular so you can swim in arcs rather than lengths; it’s rippled water is illuminated by the sun; it’s refreshed by the sea-breeze; and it’s filled with sea water. We swim, dive and play before sitting on the concrete bench to warm and dry our chilled skin in the sun.